Delustered plastic filament



Dec. 26, 1967 A. J. TLAMICHA l DELUSTERED PLASTIC FILAMENT Original Filed Sept. 25,

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(zcfnssoj @Li r HTToRnEy United States Patent Office 3,360,424 Patented Dec. 26, 1967 ABSTRACT OF THE DISCLOSURE A delustered filament made of highly molecular plastics which has substantially uniformly abraded surfaces that are formed by mechanically -abrading the same so as to leave microscopic grooves extending in mutually intersecting directions. The depth of the grooves is preferably of the order of less than 5% the diametric dimension of the filament.

The mutually intersecting grooves are obtained by passing the filament over the abrading surfaces of a rotating element at least once on each side of the axis.

The present application is a divisional application of the co-pending application Ser. No. 311,289, filed in the name of the dece-ased applicant on Sept. 23, 1963, now U.S. Patent 3,229,347.

The present invention relates to delustered mono-filaments or multi-filaments made of high molecular plastics, such as, for example, polyamide.

It is known in the prior art to guide multi-filament yarns over abrading bodies in order to tear individual filaments of the multi-twisted yarn and to abrade or roughern up in this manner the yarn for various purposes. For example, to make it appear dull. The ULS. Patent 2,244,333 to W. C. Hanse, issued June 3, 1941, is representative of such prior art apparatus and process. However, with such prior art apparatus and process, the yarn is weakened non-uniformly and its mechanical properties are significantly reduced.

Known further in the prior art is a process for roughening or abrading mono-filament or multi-filament threads of high molecular plastics, especially of polyamides as are needed in large quantities, for example, in the manufacture of ladies hose, in which the filament is t-angentially guided over a rotary abrading or roughening-body and is, as a result thereof, roughened and abraded, as disclosed in my co-pending application, Ser. No. 96,418, filed Mar. 17, 1961, now U.S. Patent 3,140,526 the contents of which are incorporated herein insofar as necessary.

The present invention relates to a delustered filament produced by a process of the type described in my aforementioned co-pending application inclusive the apparatus appert-aining thereto, in which, however, the filament is emplaced Within an axial plane upon conical surfaces provided on the abrading or roughening body at least once each at mutually opposite places and is thereby roughened or abraded in different, mutually crossing directions.

This may be, for example, achieved by guiding the filament obliquely through a hollow cylindrical abrading or roughening body. The abrading or roughening body is, accordingly, for example, a cylindrical hollow body with conically shaped end surfaces increasing in the outward direction or with hollow conical annular end surfaces that are inclined in the inward direction and rounded-ofi, or again the abrading or roughening body is an abrading disk with conically shaped, inclined circumferential surfaces or with cylindrical, circumferenital surfaces rounded-off on both sides or also with semi-circularly shaped circumferential surfaces.

By reason of the circumferential speed of the roughening or abrading body rotating at relatively high rotational speeds, the filament is slightly deviated or deflected from its feed direction whereby the filament rotates about its own axis numerous times while maintaining its circular cross section. As a result of the roughening or abrading action, obliquely or diagonally extending, microscopically fine grooves are produced on the surfaces of the very thin filaments which are produced during the first abutment against or engagement of the filament with the abrading body in the one diagonal direction and during the second abutment against or engagement of the filament at the opposite place of the abrading body in an approximately perpendicular direction with respect thereto.

Thus, a double transverse grooving of which the two sets of grooves intersect crosswise is obtained by the process in accordance with the present invention which is considerably better and more satisfactory than a roughening or abrading in a single longitudinal direction. The dulling of the surface of the filament produced by the abrading or roughening action according to the present invention is additionally much more pronounced and more intense as well as also still more uniform over the entire length of the filament having many kilometers, and light impinging thereon is equally good reflected with diffusion in all directions. Furthermore, the cross section ofthe filament is neither weakened nor, with multi-filament threads consisting of several individual filaments, are parts thereof torn so that the mechanical properties thereof are farreachingly maintained.

An object of the present invention resides in the provision of a delustered filament made of high molecular plastic materials which has a highly uniform roughened surface produced without impairing the mechanical properties of the filaments.

Another object of the present invention resides in the provision of abraded filaments of high molecular plastic materials produced by an abrading action in mutually intersecting directions to enhance the intensity of the surface dullness as well as the light diffusing and reflecting properties of the filaments.

A further object of the present invention resides in the provision of abraded filaments of high molecular plastic materials produced without tearing of the filaments during the abrading action by limiting the grooves to microscopic depths and at the same time enable continuous wetting of the filaments in minute, predetermined metered quantities.

These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein:

FIGURE 1 is a longitudinal cross-sectional view through a first embodiment of an abrading or roughening body constructed as cylindrical hollow body;

FIGURE 2 is an end elevational View body of FIGURE l;

FIGURE 3 is a partial elevational View, on a highly enlarged scale, of a filament produced in accordance with the present invention;

FIGURE 4 is an elevational view of a modified embodiment of an abrading or roughening body in accordance with the present invention constructed as abrading disk;

FIGURE 5 is an end elevational view of the abrading body of FIGURE 4;

FIGURE 6 is a longitudinal cross-sectional view through a still further modified embodiment of an abrading or roughening body in accordance with the present invention constructed as abrading disk; and

of the abrading FIGURE 7 is an end elevational view of the abrading body of FIGURE 6.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGURES 1 and 2, the abrading or roughening body of this embodiment is constructed as cylindrical hollow body 11 provided either with hollow, conically shaped, annular surfaces 12 inclined inwardly and rounded-off or with conically shaped, annular end surfaces 12 increasing outwardly. The filament 1 is guided obliquely through the hollow body 11 within an axial plane and thereby sequentially rests on or engages with the opposite end surfaces 12. The filament 1, if necessary, is thereby guided through guide eyelets 13 of any suitable construction and arranged on both sides of the abrading body 11. The hollow body 11 is, for example, surrounded by a roller bearing 14 and is suitably driven by means of a belt drive including pulley 15 from any suitable driving means, for example, an electric motor with speed-adjusting and/or speed-reversing means. The rotational speed of the hollow body 11 which is a fine-grain grinding body either throughout its entire structure or at the end surfaces 12 only, amounts up to 15,000 r.p.m. or more. A fine-grain silicon abrasive may be used with the grinding body of any one of the embodiments described herein.

The filament 1, While being guided through the rotating hollow body 11, is slightly deliected from its normal feed direction by the end surfaces 12 as shown in FIG- URE 2. As a result of this defiection which depends on the rotational speed of the hollow body 11 and on the mechanical tension in the filament 1 as well as also on the exit speed thereof, all of which may be adjusted by suitable conventional means, the filament 1 rotates itself about its own longitudinal axis. Consequently, the filament 1 is abraded or roughened on all sides during itS abutment against and engagement with the end surfaces 12 without, however, impairing or adversely alecting the original circular cross section thereof in any manner whatsoever. The guide eyelets or loops 13 and the inclined angle of the hollow, conically extending end surfaces 12 are further so arranged and dimensioned that the filament 1 passing therethrough rests flush on the surfaces 12. The abutment or engagement of the filament 1 may be adjusted, if necessary, by suitably changing the position of the guide eyelets 13.

As a result of the first abutment against or engagement with the end surfaces 12, there are imparted to the filament 1 grooves extending obliquely or diagonally to the longitudinal direction thereof which grooves, however, are only microscopically deep (FIGURE 3). As a result of the subsequent abutment against or engagement with the end surfaces 12 at the oposite place, there are also produced diagonal grooves 17 which, however, are disposed transversely to the grooves 16. In this manner, the surface of the filament 1 receives a double-transverse, mutually crossing groove configuration which remains uniform over the entire length thereof, and reflects the impinging light completely diffused so that a very intense and deep surface dullness results therefrom. With a denier filament having a diameter of approximately 48 microns the depth of the grooving 16, 17 amounts to only approximately 0.5 micron so that the rigidity properties and strength characteristics of the filament are in no Way impaired.

With the embodiment according to FIGURES 4 and 5, the abrading or roughening body is constructed as fiat abrading or roughening disk 19 mounted on the drive shaft 18. The filament 1 is guided over the circumferential surfaces 20 of the disk 19 which are inclined inwardly conically shaped and are rounded-off within an axial longitudinal plane at two mutually opposite places, that is, above and below the axis of the drive shaft 18 whereby the filament 1 is guided through correspondingly arranged guide eyelets 13. However, it is also understood that the circumferential surfaces 20 may also be of cylindrical configuration with adjoining oblique surfaces or rounded-off surfaces.

The filament 1 is taken along in the circumferential direction by the circumferential velocity of the rotating, abrading disk 19 but is not lifted-olic because this is prevented by the guide eyelets 13 provided closely adjacent to the abrading disk 19, for example, also staggered obliquely in the axial direction. Consequently, only a deflecting or bulging, that is, an inclined guiding of the filament 1 over the abutment places of the abrading disk 19 takes place so that the filament 1 is twisted in itself and is thereby abraded or roughened uniformly `and simultaneously by the resulting mutually crossing transverse grooves (FIGURE 3).

The embodiment according to FIGURES 6 and 7 also shows an abrading or roughening disk 21 mounted on a drive shaft 18 and provided with double, conically shaped inclined circumferential surfaces 22 or with cylindrical circumferential surfaces 22 rounded-off on both sides thereof, over which the filament 1 is guided at opposite places on both sides of the axis of the drive shaft 18, that is, altogether four times. In order to achieve this completely satisfactorily, the abrading or roughening disk 21 is provided in the center thereof with a circumferential trough or recess 23. Additionally the filament is so guided through guide eyelets 13 in the axial longitudinal plane that it abuts sequentially flush against the various places of the circumferential surfaces 22 either bulged or diagonally. The circumferential recess 23 is only provided for the accommodation of the centrally arranged guide eyelets 13. The operation of the embodiment of FIG- URES 6 and 7 is the same as that of the embodiment of FIGURES 4 and 5.

In the embodiment of FIGURES 6 and 7, a nozzle 24 is additionally provided which etxends into a dish-shaped or ring-shaped bore or recess 26 at one of the two end faces of the abrading disk 21 and through which a liquid 25, for example, water, may be dripped onto the abrading disk. It is possible in this manner to wet the rotating abrading disk 21 continuously from the inside thereof. By reason of the centrifugal force, the liquid 25 leaves through the circumferential surfaces 22 in minute drops so that the pores of the abrading disk 21 are continuously cleansed by fiushing of the abrasion or dust produced by the abrading or roughening of the filament 1. It is, of course, also within the purview of the present invention to supply the liquid 25 on both sides of the abrading disk 22 or to provide a similar wetting system in the embodiment of FIGURES 4 and 5 and 1 and 2.

The threads to which the present invention apply are, as mentioned above, mono-filament or multi-filament threads of highly molecular plastics, especially polyamides, Hence, the term filaments as used herein and in the appended claims is to be considered directed to such monoand multi-filament threads.

While I have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications within the spirit and scope thereof; and I, therefore, do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications aS are encompassed by the scope of the appended claims.

What is claimed is:

1. A delustered filament made of highly molecular plastics, characterized in that the surfaces thereof are provided substantially unformly on all sides and over the entire length thereof with two sets of mechanically abraded microscopic and mutually intersecting grooves, the grooves of the respective sets forming oppositely directed angles with respect to an axial cross-sectional plane through the filament.

2. A delustered filament made of highly molecular plastics, characterized in that the surfaces thereof are provided substantially uniformly on al1 sides and over the entire length thereof with two sets of mechanically abraded microscopic and mutually intersecting grooves, the grooves of the respective sets forming oppositely directed angles with respect to an axial cross-sectional plane through the filament, the grooves having a depth of the order of less than 5% the diametric dimension of the lament.

3. A delustered filament made of highly molecular plastics, characterized in that the surfaces thereof are provided substantially uniformly on al1 sides and over the entire length thereof with two sets of mechanically abraded microscopic and mutually intersecting grooves, the grooves of the respective sets forming oppositely di- References Cited UNITED STATES PATENTS 5/1934 Taylor 161-180 X 12/1964 Tlamicha 161-180 X 0 ROBERT F. BURNETT, Primary Examiner.

ALEXANDER WYMAN, Examiner.

R. H. CRISS, Assistant Examiner. 

1. A DELUSTERED FILAMENT MADE OF HIGHLY MOLECULAR PLASTICS, CHARACTERIZED IN THAT THE SURFACES THEREOF ARE PROVIDED SUBSTANTIALLY UNFORMLY ON ALL SIDES AND OVER THE ENTIRE LENGTH THEREOF WITH TWO SETS OF MECHANICALLY ABRADED MICROSCOPIC AND MUTUALLY INTERSECTING GROOVES, THE GROOVES OF THE RESPECTIVE SETS FORMING OPPOSITELY DIRECTED ANGLES WITH RESPECT TO AN AXIAL CROSS-SECTIONAL PLANE THROUGH THE FILAMENT. 